A cable operator, or any communication or content distribution business that operates through a cable network, renders its services to its subscribers. The services include, but are not limited to, different subscription plans for broadband Internet access and telephony. Each subscription is typically tied to a specific address where the service is received.
In order to consume these services, subscribers connect to a private network owned (or co-owned or rented) by the cable operator which is implemented according to the Data Over Cable Service Interface Specification (DOCSIS for short) standard.
Subscribers connect their computers, routers, voice-over-IP telephones and other devices to this network through the network terminals, called cable modems. A cable modem (CM for short) is a piece of hardware which runs a form of software that is referred to as firmware. This firmware is developed by the different cable modem vendors (e.g., Cisco, Arris) and distributed to the cable operators. The firmware may contain bugs or lack features, and the cable modem vendors will develop and distribute new firmware versions. In turn, a cable operator will receive firmware updates, and evaluate whether he wants to approve (or homologate) a new firmware version and push the firmware update to its subscribers.
The cable operator usually provides cable modems, typically coming from a variety of cable modem vendors and in different models and versions, to its subscribers upon subscription. At the time of delivering the cable modem to a new subscriber, the cable operator can ensure that it is running the latest version of firmware that has been homologated. Subscribers may provide a cable modem by their own means. The cable operator issues (approved and) updated versions of the firmware from time to time that it needs to roll out to its complete subscriber population to which the update applies (as an example, to all Cisco cable modems). Deploying these new firmware versions and ensuring that the complete subscriber population performs the update successfully, is typically problematic. While not inclusive of all reasons, a few problematic reasons follow.
First, the population of cable modems consists of a heterogeneous mix of manufacturer's, hardware and firmware versions, which the cable operator may not be able to track accurately. Consequently, the cable operator may not be able to create tests and ensure that the updates will work for all the population. The updates are prone to failure in these exceptional cases.
Second, no matter what action the cable operator takes, it cannot enforce updates. For example, a particular subscriber could have disconnected his CM during a long period of absence or he may use a cable modem which has been modified in some way so that remote management operations, and in particular updates, fail. The cable operator must then track the successful firmware updates, the failed updates and the CMs that have not been updated.
Third, the network and its equipment are not prepared for servicing all the updates simultaneously, as there may be bottlenecks at different stages of an update. These bottlenecks may cause updates to fail or get postponed and have a negative impact in service—for example by reducing the quality of the broadband service that subscribers are paying for.
Fourth, during a cable modem's update procedure, the cable modem must be rebooted and then the services it renders get interrupted. What is more, when these cable modems also provide telephony, an ongoing phone conversation could be dropped. Since the cable operator wants to limit unavailability, in particular when a telephone conversation is taking place, he must choose the updating moment with additional care so it becomes imperceptible to the subscribers.
Fifth, the cable operators have grown a complex and expensive platform to support their business, so that any solution to the firmware update problem will need to be compliant with the platform.
Sixth, when the service is reestablished after a cable modem termination system (CMTS) or network outage, many cable modems will reconnect and might be forced to update by a standard update solution. Yet, updating all these cable modems in an uncoordinated fashion would imply a heavy resource consumption with an unsatisfactory impact to subscribers.
Seventh, cable operators will release both firmware updates and also changes in the configuration files. The cable modems will load these configuration changes when rebooting. A faulty firmware may cause the cable modem to reboot several times and cause discomfort in the subscribers. A faulty configuration may cause the upgrade to fail, and the cable modem to reboot using the old configuration. The cable operator must be prepared to detect these problems and rollback the configuration change before it continues to impact other subscribers. These kinds of problems are often tackled by cable operators by a manual and tedious procedure where reboots are manually monitored.
Thus, a heretofore unaddressed need exists in the industry to address the aforementioned deficiencies and inadequacies.